EXPERIMENT STATION BULLETINS. 



181 



exceeding twenty-five or thirty cents for an average-size tree. Tliis 

 estimate will cover the cost of the chemicals and of their application, and 

 if the season is a warm, dry one, and the chemicals are purchased at whole- 

 sale it can Be reduced one half. 



GEEENHOUSE CONSTKUCTIOX AND HEATING. 



Balletin No. 63. 



For a number of years the work of this department has been handicapped 

 by want of proper forcing houses in which to start the plants required for 

 experimental and other purposes. 



To remedy this, the Board of Agriculture, in August, 1889, authorized 

 the erection of two houses, each 50 by 20 feet, together with suitable work- 

 rooms, furnace rooms, etc. ; and in September the work commenced. 



The site selected was just within the limits of the vegetable garden, and 

 about one hundred feet southeast from the Horticultural Laboratory ; a spot 

 centrally located for oiir work, and one where the force of the wind was 

 broken by buildings and large evergreens. 



As they were to be considered experimental forcing houses, it was 

 thought best to make them, so far as was possible, experimental in their 

 construction, by combining in them various methods of glazing, heating, 

 and ventilating. 



The style of house selected as being best suited to our wants and sur- 

 roundings, was the common even span, as shown in the engraving, ( Fig. 1 ) 



(Fig. 1. — General view of Forcing Houses with Horticultural Laboratori/ in the distance.) 



